In wireless communications systems, antenna arrays are used as an efficient means to transmit a large amount of information in a single signal. An antenna array is a group of spaced apart antennas that can work cooperatively to transmit a signal from a transmitting device to a receiving device. When working cooperatively to transmit a signal, an antenna array produces a unique antenna pattern that is more focused on a receiving device than would be a single antenna.
Antenna arrays can produce many different antenna patterns depending on the operating parameters used with individual antennas. The best antenna pattern to use for a particular transmission is variable and depends on factors, such as the nature of the transmission, the type of receiving device, the location and conditions surrounding the transmitting device, the location and conditions surrounding the receiving device, and so on. To enhance the capabilities of antenna arrays, many wireless systems provide mechanisms by which wireless devices can send antenna feedback to base stations. The antenna feedback allows a receiving device to request a particular antenna pattern from a base station.
Current antenna feedback schemes operate such that wireless devices repeatedly transmit antenna feedback to base stations regardless of whether they are receiving data or not. These schemes waste system resources and bandwidth used for this unneeded feedback. Accordingly, an approach is needed that provides for the on demand transmission of antenna feedback from a receiving device to a transmitting device.